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From: Rasmus Villemoes <linux@rasmusvillemoes.dk>
To: Peter Zijlstra <peterz@infradead.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>, Khalid Aziz <khalid.aziz@oracle.com>,
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Subject: Re: [RFC] [PATCH] Pre-emption control for userspace
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Date: Thu, 06 Mar 2014 14:45:00 +0100
In-Reply-To: <20140306133450.GL9987@twins.programming.kicks-ass.net> (Peter
	Zijlstra's message of "Thu, 6 Mar 2014 14:34:50 +0100")
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Peter Zijlstra <peterz@infradead.org> writes:

> On Thu, Mar 06, 2014 at 02:24:43PM +0100, Rasmus Villemoes wrote:
>> Is it possible to implement non-sleeping versions of {get,put}_user()?
>
> __{get,put}_user()

Huh?

arch/x86/include/asm/uaccess.h:

/**
 * __get_user: - Get a simple variable from user space, with less checking.
 * @x:   Variable to store result.
 * @ptr: Source address, in user space.
 *
 * Context: User context only.  This function may sleep.

What am I missing?

Rasmus